Add bunk beds

[mokun]

Is your feature request related to a problem? Please describe.

• Currently, every bed is a single bed.
• We should at least have bunk beds and also large beds for future couples .

Describe the rationale

• Bunk beds would allow better use of compact space in a module.
• In future, when we create non-descript work crew (ones who would not need names), then bunk beds would be a lot of handy.

Describe the goal(s) you have in mind

• Set up a production line for furniture. This way, we can make different types of beds such as single beds vs bunk beds
• We need a different svg image for bunk beds vs. single beds.

Describe the solution you desire to see

• If we can replace the chunk of code for drawing a bed in an svg image file, then we can replace a single bed with bunk bed
• In terms of location of a person when sleeping, we may need to create a more opaque dot for one sleeping at the lower level of a bunk bed and a more less opaque dot for one sleeping at the high level.

Specifications

• post 3.7. 0 build 9162

Additional context

• Bunk beds may be assigned for those lower in rank.